US4859906A - Deep UV lamp bulb with improved fill - Google Patents

Deep UV lamp bulb with improved fill Download PDF

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Publication number
US4859906A
US4859906A US06/433,069 US43306982A US4859906A US 4859906 A US4859906 A US 4859906A US 43306982 A US43306982 A US 43306982A US 4859906 A US4859906 A US 4859906A
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US
United States
Prior art keywords
bulb
envelope
deep
lamp
microwave energy
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
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US06/433,069
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English (en)
Inventor
Michael G. Ury
Charles H. Wood
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Fusion Systems Corp
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Fusion Systems Corp
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Priority to US06/433,069 priority Critical patent/US4859906A/en
Assigned to FUSION SYSTEMS CORPORATION reassignment FUSION SYSTEMS CORPORATION ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: URY, MICHAEL, WOOD, CHARLES H.
Priority to JP58185219A priority patent/JPS5987751A/ja
Priority to DE19833336473 priority patent/DE3336473A1/de
Application granted granted Critical
Publication of US4859906A publication Critical patent/US4859906A/en
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    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
    • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
    • G03F7/70—Microphotolithographic exposure; Apparatus therefor
    • G03F7/70008—Production of exposure light, i.e. light sources
    • G03F7/70016—Production of exposure light, i.e. light sources by discharge lamps
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J65/00—Lamps without any electrode inside the vessel; Lamps with at least one main electrode outside the vessel
    • H01J65/04—Lamps in which a gas filling is excited to luminesce by an external electromagnetic field or by external corpuscular radiation, e.g. for indicating plasma display panels
    • H01J65/042—Lamps in which a gas filling is excited to luminesce by an external electromagnetic field or by external corpuscular radiation, e.g. for indicating plasma display panels by an external electromagnetic field
    • H01J65/044—Lamps in which a gas filling is excited to luminesce by an external electromagnetic field or by external corpuscular radiation, e.g. for indicating plasma display panels by an external electromagnetic field the field being produced by a separate microwave unit

Definitions

  • the present invention is directed primarily to an improved lamp bulb for use in a deep ultraviolet light source, and also to a source which incorporates the improved bulb.
  • UV photolithography An important use for deep ultraviolet (deep UV) light sources presently is in the practice of semiconductor photolithography.
  • a pattern in an optical mask which corresponds to the features of an integrated circuit to be manufactured is imaged on to a semiconductor wafer which ha been coated with a UV sensitive photoresist with ultraviolet light at conventional wavelengths (260-460 nm). After the pattern is exposed on the wafer, it undergoes further processing, and ultimately results in a transistor device or integrated circuit.
  • Such prior electrodeless bulbs include the linear bulbs for industrial curing manufactured by Fusion Systems Corporation, Rockville, Md., and the spherical and other geometrically shaped electrodeless bulbs disclosed in U.S. Pat. Nos. 3,943,402; 3,943,401; 4,185,228; 3,942,058; 3,993,927; and 4,001,031. All of the above-mentioned bulbs utilize a mercury fill wherein the mercury is present in specific volumetric proportion to bulb volume.
  • the invention is based on the discovery that the volume of mercury which is contained in the lamp bulb is critical for effective deep UV operation.
  • a mercury fill having a volume ratio of 0.5-0.9 ⁇ l per ml of bulb volume at room temperature (72° F.) is provided.
  • the above-mentioned mercury fill ratio also results in a relatively small skin depth in the bulb, so that a substantial portion of the ultraviolet radiation is emitted at the outer radii of the bulb, thereby minimizing deep UV absorption by the body of the plasma and the neutral boundary layer which separates the plasma from the envelope wall.
  • FIG. 1 is a schematic representation of an embodiment of an electrodeless lamp.
  • FIG. 2 is a graph of mercury fill ratio versus deep UV output for the electrodeless lamp bulb of FIG. 1.
  • FIG. 3 is a schematic representation of an embodiment of an electrodeless light source incorporating the bulb of the invention.
  • FIG. 4 is a schematic representation of a cooling system for the light source of FIG. 3.
  • Lamp bulb 1 is depicted, and is shown being attached to mounting stem 3.
  • Lamp bulb 1 consists of envelope 2 of spherical or other shape, which contains a fill comprised primarily of mercury, a noble gas, and a substance such as HgCl which serves to keep the discharge off the envelope wall during operation.
  • the volumetric ratio of mercury in the bulb is critical for producing a bright output with high deep UV spectral content.
  • a deep UV lamp bulb having a mercury fill therein in a volume ratio of 0.5-0.9 ⁇ l per ml of envelope volume at room temperature is provided. It is significant to note that the critical range of 0.5-0.9 ⁇ l/ml was arrived at after the dynamics of bulb physics were analyzed.
  • FIG. 2 is a graph of deep UV relative bulb
  • volumetric ratio of mercury was varied by applicants in order to obtain the information depicted in FIG. 2, to define the critical range of volumetric ratios for the deep UV output depicted. It is only by using a ratio falling within this critical range that a suitable lamp bulb for performing deep UV photolithography can be provided. While the data depicted in FIG. 2 is for a bulb having an internal diameter of 18.5 mm it is significant to note that the critical volumetric ratio is independent of bulb diameter and bulb geometry.
  • the skin depth ⁇ the distance from the envelope into the bulb over which microwave energy is absorbed, to be as small as possible.
  • a quartz envelope 18.5 mm in diameter is filled with 2.1 ⁇ l of Hg, including argon at 90 torr and also may include a small amount of HgCl 2 , about 0.1 mg.
  • the envelope is made of water-free, synthetic quartz for long operational lifetime, which is described in greater detail in co-pending U.S. application Ser. No. 433,070, assigned to the same assignee as the present application.
  • the light source is comprised of microwave chamber 4 and electrodeless lamp bulb 6, which is disposed in the chamber.
  • the lamp bulb envelope is arranged to have a maximum dimension which is substantially smaller than a wavelength of the microwave energy utilized to excite the plasma in the bulb, and chamber 4 has a slot 8 for efficiently coupling microwave energy to the bulb.
  • the microwave energy is supplied by magnetron 10 which is activated by a power supply 12, and the microwave energy generated by the magnetron is fed through rectangular waveguide section 14 tunable by tuning stub 16, to the slot 8 in microwave chamber 4.
  • chamber 4 The interior of chamber 4 is coated with a UV reflective material and the chamber has an opening 18 for allowing deep ultraviolet radiation which is emitted by the lamp bulb to pass out of the chamber.
  • the opening is covered with metallic mesh 20 which is substantially transparent to the emitted ultraviolet radiation, but substantially opaque to the microwave energy within the chamber.
  • the chamber is arranged to be near-resonant, but not resonant as calculated for an ideal chamber without a bulb present. It has been found that a condition of near-resonance results in maximum coupling of energy to the small bulb 6, and consequently maximum light output therefrom.
  • the chamber is arranged to be near-resonant at a single wavelength rather than at a multiple of wavelengths, which facilitates efficient absorption of the microwave energy.
  • the relative, positioning of the slot 8 and opening shown in FIG. 3 provide a relatively uniform UV output through mesh 20.
  • Magnetron 10 provides about 1500 watts of microwave power at a frequency 2450 Mhz, and a major part of this power is coupled to the plasma, resulting in a power density of approximately 500 watts/cc.
  • the resulting light source has a conversion efficiency in the deep UV part of the spectrum of about 8%, and is a bright source which radiates at about 190 watts/cc.
  • the high power density at which the lamp is operated causes the surface of the quartz envelope of bulb 6 to become extremely hot.
  • a cooling system is employed wherein the envelope is rotated while a plurality of jets of cooling gas are directed at it.
  • lamp envelope 6 has a stem 29 which is rotated by motor 23.
  • the motor shaft is connected to stem 29 via a mechanical coupler so that the stem is effectively an extension of the motor shaft, and also in FIG. 3 a mechanical configuration using flange 21, motor mounting flange 24, and spacing posts 22 is illustrated.
  • FIG. 4 shows the system for directing cooling gas at the envelope as it rotates, and is seen to depict nozzles 40, 42, 44, and 46, which are fed by compressed air supply 38.
  • the nozzles are directed approximately at the center of the envelope and combine with the rotation to provide a substantial cooling effect.
  • all of the nozzles are located in a plane which passes through the center of the sphere.
  • bulbs having a diameter of 1 inch or larger more effective cooling may be obtained if the nozzle 40 is offset slightly to one side of the chamber center plane while nozzle 42 is offset slightly to the other side, and similarly for nozzles 44 and 46.
  • metallic chamber 4 is a 3.9 inch diameter sphere having a 2.8 inch circular opening which is covered by mesh 20.
  • Mesh 20 is a grid of 0.0017 inch diameter wires having a spacing of 0.033 inches between wire centers.
  • Spherical lamp envelope 6 is 18.5 mm in interior diameter and is filled with 2.1 ⁇ l of Hg, a noble gas such as argon at 90 torr and may include a small amount of HgCl 2 , about 0.1 mg.

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • Electromagnetism (AREA)
  • General Physics & Mathematics (AREA)
  • Discharge Lamps And Accessories Thereof (AREA)
US06/433,069 1982-10-06 1982-10-06 Deep UV lamp bulb with improved fill Expired - Lifetime US4859906A (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
US06/433,069 US4859906A (en) 1982-10-06 1982-10-06 Deep UV lamp bulb with improved fill
JP58185219A JPS5987751A (ja) 1982-10-06 1983-10-05 改善された充填材を有する遠ｕｖ線電球
DE19833336473 DE3336473A1 (de) 1982-10-06 1983-10-06 Elektrodenlose uv-lampe

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US06/433,069 US4859906A (en) 1982-10-06 1982-10-06 Deep UV lamp bulb with improved fill

Publications (1)

Publication Number Publication Date
US4859906A true US4859906A (en) 1989-08-22

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US (1) US4859906A (enrdf_load_stackoverflow)
JP (1) JPS5987751A (enrdf_load_stackoverflow)
DE (1) DE3336473A1 (enrdf_load_stackoverflow)

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4950059A (en) * 1988-10-11 1990-08-21 General Electric Company Combination lamp and integrating sphere for efficiently coupling radiant energy from a gas discharge to a lightguide
US4975625A (en) * 1988-06-24 1990-12-04 Fusion Systems Corporation Electrodeless lamp which couples to small bulb
USRE34492E (en) * 1988-10-11 1993-12-28 General Electric Company Combination lamp and integrating sphere for efficiently coupling radiant energy from a gas discharge to a lightguide
US5798611A (en) * 1990-10-25 1998-08-25 Fusion Lighting, Inc. Lamp having controllable spectrum
US5834895A (en) * 1990-10-25 1998-11-10 Fusion Lighting, Inc. Visible lamp including selenium
EP0754976A3 (en) * 1995-07-11 1999-06-02 Ushiodenki Kabushiki Kaisha Surface activating process, and device and lamp for performing said process
US5910710A (en) * 1996-11-22 1999-06-08 Fusion Lighting, Inc. Method and apparatus for powering an electrodeless lamp with reduced radio frequency interference
WO2003002615A1 (en) * 2001-06-27 2003-01-09 Fusion Uv Systems, Inc. Free radical polymerization method having reduced premature termination, apparatus for performing the method, and product formed thereby
US6597003B2 (en) 2001-07-12 2003-07-22 Axcelis Technologies, Inc. Tunable radiation source providing a VUV wavelength planar illumination pattern for processing semiconductor wafers
US20040259665A1 (en) * 2003-06-17 2004-12-23 Sullivan Michael J. Golf ball comprising UV-cured non-surface layer
US20070272098A1 (en) * 2003-12-19 2007-11-29 Acushnet Company Method of printing golf balls with radiation curable ink
US20100283390A1 (en) * 2009-04-28 2010-11-11 Auer Lighting Gmbh Plasma lamp

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63234529A (ja) * 1987-03-24 1988-09-29 Ushio Inc レジスト処理方法
DE3823766A1 (de) * 1987-07-15 1989-01-26 Fusion Systems Corp Verfahren und vorrichtung zum aendern der emissionseigenschaften einer elektrodenlosen lampe

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3521111A (en) * 1965-10-01 1970-07-21 Mitsubishi Electric Corp Discharge lamp having a fill including mercury and gallium iodide
US3786308A (en) * 1972-03-06 1974-01-15 Regents Board Of Temperature stabilized spectral source
GB1351280A (en) * 1970-02-24 1974-04-24 Shandon Southern Instr Ltd Discharge lamps
US3873884A (en) * 1973-03-01 1975-03-25 Perkin Elmer Corp Electrodeless discharge lamp and power coupler therefor
SU469166A1 (ru) * 1973-07-12 1975-04-30 Предприятие П/Я Р-6681 Водородна спектральна лампа
US3943402A (en) * 1975-04-21 1976-03-09 Gte Laboratories Incorporated Termination fixture for an electrodeless lamp
US4001632A (en) * 1975-04-21 1977-01-04 Gte Laboratories Incorporated High frequency excited electrodeless light source
DE2845890A1 (de) * 1977-12-23 1979-06-28 Ushio Electric Inc Quecksilber-edelgas-entladungslampe
JPS55113252A (en) * 1979-02-26 1980-09-01 Tokyo Denshi Giken Kk Ultraviolet rays generator by microwave
US4427921A (en) * 1981-10-01 1984-01-24 Gte Laboratories Inc. Electrodeless ultraviolet light source

Family Cites Families (11)

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Publication number Priority date Publication date Assignee Title
US4001631A (en) * 1975-04-21 1977-01-04 Gte Laboratories Incorporated Adjustable length center conductor for termination fixtures for electrodeless lamps
US3993927A (en) * 1975-04-21 1976-11-23 Gte Laboratories Incorporated Electrodeless light source
US3943401A (en) * 1975-04-21 1976-03-09 Gte Laboratories Incorporated Electrodeless light source having a lamp holding fixture which has a separate characteristic impedance for the lamp starting and operating mode
US3942058A (en) * 1975-04-21 1976-03-02 Gte Laboratories Incorporated Electrodeless light source having improved arc shaping capability
US3943403A (en) * 1975-04-21 1976-03-09 Gte Laboratories Incorporated Electrodeless light source utilizing a lamp termination fixture having parallel capacitive impedance matching capability
US4042850A (en) * 1976-03-17 1977-08-16 Fusion Systems Corporation Microwave generated radiation apparatus
US4185228A (en) * 1978-10-19 1980-01-22 Gte Laboratories Incorporated Electrodeless light source with self-contained excitation source
JPS55102169A (en) * 1979-01-31 1980-08-05 Oak Seisakusho:Kk Ultraviolet ray generator
JPS56141165A (en) * 1980-04-04 1981-11-04 Mitsubishi Electric Corp Nonelectrode electric discharge lamp
US4532427A (en) * 1982-03-29 1985-07-30 Fusion Systems Corp. Method and apparatus for performing deep UV photolithography
JPS58194247A (ja) * 1982-05-07 1983-11-12 Mitsubishi Electric Corp マイクロ波放電光源装置

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3521111A (en) * 1965-10-01 1970-07-21 Mitsubishi Electric Corp Discharge lamp having a fill including mercury and gallium iodide
GB1351280A (en) * 1970-02-24 1974-04-24 Shandon Southern Instr Ltd Discharge lamps
US3786308A (en) * 1972-03-06 1974-01-15 Regents Board Of Temperature stabilized spectral source
US3873884A (en) * 1973-03-01 1975-03-25 Perkin Elmer Corp Electrodeless discharge lamp and power coupler therefor
SU469166A1 (ru) * 1973-07-12 1975-04-30 Предприятие П/Я Р-6681 Водородна спектральна лампа
US3943402A (en) * 1975-04-21 1976-03-09 Gte Laboratories Incorporated Termination fixture for an electrodeless lamp
US4001632A (en) * 1975-04-21 1977-01-04 Gte Laboratories Incorporated High frequency excited electrodeless light source
DE2845890A1 (de) * 1977-12-23 1979-06-28 Ushio Electric Inc Quecksilber-edelgas-entladungslampe
JPS55113252A (en) * 1979-02-26 1980-09-01 Tokyo Denshi Giken Kk Ultraviolet rays generator by microwave
US4427921A (en) * 1981-10-01 1984-01-24 Gte Laboratories Inc. Electrodeless ultraviolet light source

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
Browner et al., "Improvements in Electrodeless Discharge Lamp Radiant Flux and Stability by Precise Temperature Control", Pittsburgh Conf. on Anal. Chem. and Appl. Spectroscopy, Cleveland, Mar. 7, 1972.
Browner et al., Improvements in Electrodeless Discharge Lamp Radiant Flux and Stability by Precise Temperature Control , Pittsburgh Conf. on Anal. Chem. and Appl. Spectroscopy, Cleveland, Mar. 7, 1972. *

Cited By (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4975625A (en) * 1988-06-24 1990-12-04 Fusion Systems Corporation Electrodeless lamp which couples to small bulb
US4950059A (en) * 1988-10-11 1990-08-21 General Electric Company Combination lamp and integrating sphere for efficiently coupling radiant energy from a gas discharge to a lightguide
USRE34492E (en) * 1988-10-11 1993-12-28 General Electric Company Combination lamp and integrating sphere for efficiently coupling radiant energy from a gas discharge to a lightguide
US5798611A (en) * 1990-10-25 1998-08-25 Fusion Lighting, Inc. Lamp having controllable spectrum
US5834895A (en) * 1990-10-25 1998-11-10 Fusion Lighting, Inc. Visible lamp including selenium
US5866980A (en) * 1990-10-25 1999-02-02 Fusion Lighting, Inc. Sulfur/selenium lamp with improved characteristics
EP0754976A3 (en) * 1995-07-11 1999-06-02 Ushiodenki Kabushiki Kaisha Surface activating process, and device and lamp for performing said process
US5910710A (en) * 1996-11-22 1999-06-08 Fusion Lighting, Inc. Method and apparatus for powering an electrodeless lamp with reduced radio frequency interference
WO2003002615A1 (en) * 2001-06-27 2003-01-09 Fusion Uv Systems, Inc. Free radical polymerization method having reduced premature termination, apparatus for performing the method, and product formed thereby
US7407617B2 (en) 2001-06-27 2008-08-05 Fusion Uv Systems, Inc. Free radical polymerization method having reduced premature termination, apparatus for performing the method, and product formed thereby
US20050032926A1 (en) * 2001-06-27 2005-02-10 Okamitsu Jeffrey K. Free radical polymerization method having reduced premature termination, apparatus for performing the method, and product formed thereby
US6908586B2 (en) 2001-06-27 2005-06-21 Fusion Uv Systems, Inc. Free radical polymerization method having reduced premature termination, apparatus for performing the method and product formed thereby
US7037460B2 (en) 2001-06-27 2006-05-02 Fusion Uv Systems, Inc. Free radical polymerization method having reduced premature termination, apparatus for performing the method, and product formed thereby
US20060116436A1 (en) * 2001-06-27 2006-06-01 Fusion Uv Systems, Inc. Free radical polymerization method having reduced premature termination, apparatus for performing the method, and product formed thereby
US6597003B2 (en) 2001-07-12 2003-07-22 Axcelis Technologies, Inc. Tunable radiation source providing a VUV wavelength planar illumination pattern for processing semiconductor wafers
US20040259665A1 (en) * 2003-06-17 2004-12-23 Sullivan Michael J. Golf ball comprising UV-cured non-surface layer
US20070082754A1 (en) * 2003-06-17 2007-04-12 Acushnet Company Golf ball comprising UV-cured non-surface layer
US7198576B2 (en) 2003-06-17 2007-04-03 Acushnet Company Golf ball comprising UV-cured non-surface layer
US8025592B2 (en) 2003-06-17 2011-09-27 Acushnet Company Golf ball comprising UV-cured non-surface layer
US20070272098A1 (en) * 2003-12-19 2007-11-29 Acushnet Company Method of printing golf balls with radiation curable ink
US20100283390A1 (en) * 2009-04-28 2010-11-11 Auer Lighting Gmbh Plasma lamp

Also Published As

Publication number Publication date
DE3336473C2 (enrdf_load_stackoverflow) 1988-05-26
JPH0423378B2 (enrdf_load_stackoverflow) 1992-04-22
DE3336473A1 (de) 1984-05-03
JPS5987751A (ja) 1984-05-21

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